The second 50 million is always the hardest part.
Online streaming music service iHeartRadio, run by terrestrial radio giant iHeartMedia, said Thursday it now has more than 100 million registered users. The service reached the 50 million mark in June 2014.
Note that registered users is not the same as monthly active users, the industry standard reported by iHeart's competitors such as Pandora and Spotify. Monthly active users are those who use a service at least once in a particular month, while registered users is a measure of people who have simply signed up for a service.
The milestone follows the January launch of iHeart's paid subscription service: the $5-a-month Plus to replay or skip songs and the $10-a-month All Access to unlock all-you-can-eat tunes. It hasn't released subscriber numbers for the service yet.
To celebrate the growth, the service launched a top 100 live radio station, the iHeart100, highlighting listeners' top songs on the service.